Automatic train-control system



W. K. HOWE.

AUTOMATIC TRAIN CONTROL SYSTEM. APPLICATION'FILED OCT. 28,1916- RENEWED JUNE 25.192I.

Patented Jan. 31, 1922'.

2 SHEETS-SHEET I,

. Zwfdfl a wwb. G

mg a

A TTOR/VE V W. K. HOWE.

AUTOMATIC TRAIN CONTROL SYSTEM. APPLICATION FILED OCT. 25. 1916. RENEWED JUNE 25. I921.

1 45 3?6 Patented Jan. 31, 1922.,

2 SHEETSSHEET 2- Ass;

ATTOR/Vfy UNlTED SATES PATENT OFFICE.

wmrnnor K. HOWE, or ROCHESTER,.NEW YORK, ASSIGNOR TO GENERAL RAILWAY SIGNAL COMIPANY, or GATES, NEW YORK, A CORPORATION or NEW YORK.

' Specification of Letters Patent.

Patented Jan. 31, 1922.

Application filed October 28, 1916, Serial No. 128,182. Renewed June 25, 1921. Serial No. 480,461.

To all whom it mag 0012061 12,:

Be it known that I, lVIN'rHnoP K. HOWE, a citizen of the United States, and resident of the city of Rochester, in the county of 5 Monroe and State of New York, have invented anew and useful Automatic Train- Control System, of which the following is a specification.

This invention relates to systems for automatically controlling the movement of railway trains and vehicles, and more particularly to systems for controlling the speed of railway trains.

In one type of systems for automatically 5 controlling the speed of railway vehicles, to

which type this invention particularly relates, the arrangement and construction of parts is such that a certain controlling effect is produced which tends to initiate the 0peration of the train control apparatus on a vehicle as it passes certain control points along the track, and at the same time a traffic controlled impulse is transmitted to the vehicle which will act to nullify this controlling effect and to prevent the initiation of the operation of the train controlled apparatus providing tratlic conditions are such that it is proper for the vehicle to proceed without having said train control apparatus set into operation. It is apparent that it is very important that the initiation of the lr,v, .r uhmopel a tipn of the train control apparatus should always occurwlientrafiic conditions require, and since this initiation is dependent upon the proper operation of one or more devices, it becomes desirable to check the operation of these devices so that it is assured that the train control apparatus will be set into operation at each control point along the track when traffic conditions require.

lVith these considerations in view, one of the principal objects of this invention is to devise an arrangement and construction of parts in automatic train control systems which will operate to check the operation of the devices controlling the train control ap paratus on a vehicle so that failure of these devices to operate properly will be immediately detected and manifested in some suitable manner.

A further object of the invention is to devise an arrangement and construction of parts in automatic train control systems such that the train control apparatus on each of several vehicles in a train may be simultaneously controlled electrically by means of a circuit connecting the vehicles, and further such that a cross or improper electrical conphysical embodiment of my invention, and

wherein like characters of reference designate corresponding parts throughout the several views, and in which:

Fig, l is a diagrammatic View, partly in the nature of a wiring diagram, which illustrates in a simplified form the parts and electrical circuits of the train control systcm carried by the vehicle and constituting one embodiment of this invention, said parts and circuits being illustrated more w1th a view of making their functions and operations clearly understood than with regard to their exact construction and arrangement; and Fig. 2 is a diagrammatic view which shows a stretch of track provided with trackway controlling circuits suitable-for controlling the operation of the train control system embodying this invention, and which also shows two vehicles on a certain portion of said stretch of track and each equipped with the parts and electrical circuits as shown in Fig. 1.

Referring to the accompanying drawing, the numerals 1 and 2 designate the track 5 rails of the ordinary railroad track; and for simplicity the vehicles are illustrated as pairs of wheels and axles without the usual bodies or frames. Referring to Fig. 2, two vehicles, such as a motor car or locomotive, each equipped with the train control system embodying the invention are shown, and for convenience the corresponding parts of these two vehicles are given the same reference characters with the distinctive exponent 1 added thereto. Each vehicle comprises a pair of wheels 3-4 connected by the usual axle 5, and a second pair of wheels 6-7 connected by an axle 8; and for simplicity thetwo vehicles shown in Fig. 2 are illustrated as coupled together by a bar 9. The connection between the two pairs of wheels and axles shown as constituting a vehicle is illustrated as obtained by two sidebars 10.

According to the embodiment of the invention illustrated, communication between the track and the vehicle necessary for the control of the train control system is obtained by the mechanical and electrical cooperation of a contact shoe carried by the vehicle with ramps or contact rails located- "compression spring 12 interposed between the side-bar 10 and a collar 13 fixed to said shoe. The contact shoe 11 is designed to open a circuit when lifted by its engagement with aramp and to perform this function the shoe 11 is shown as provided with a button 14 of suitable insulating material, which is larger than the stem portion of said shoe and which is adapted to form a stop for limiting the downward movement of said shoe; and this button 14 is arranged so as to lift a contact spring 15 out of electrical contact with a contact piece 16 when said shoe 11 is raised.

The ramps with which the shoe 11 engages may be of any suitable construction and in general comprise metallic contacting portions having sloping ends, said ramps being fixed to suitable insulating supports adjacent to one of the track rails so as to be in posi-' tion to be engaged by the contact shoe 11 on a passing vehicle. These ramps are illustrated conventionally and are designated R. Associated with each ramp R is a source 'of electrical energy and circuits for establishing a difierence of potential between that ramp and a track rail. In Fig. 1, this source of current is shown as a transformer T which has one terminal of its secondary connected by the conductor 17 to the track rail 2 and its other terminal by conductor 18, switch 19 and conductor 20 to the ramp R. A conductor 21 is connected to an intermediate tap of the secondary of said trans former T and is arranged to be contacted by the switch 19. lit is apparent that the simplified arrangement shown in Fig. 1 profor establishing a difi'erence of potential between the track rail 2 and the ramp R equivalent to the entire voltage of the secondary of the transformer T, for establishing a difference of potential equivalent to only part of the voltage of said secondary, and for discontinuing both differences of potential. For convenience these electrical conditions of a. ramp R will be hereinafter termed high voltage on the ramp, low voltage on the ramp, and zero voltage on the ramp, respectively.

Referring to Fig. 1, the simplified form of train control apparatus comprises a worm 22 fixed to the axle 5 and meshing with a worm wheel 23 secured to a shaft 24 which is mounted in suitable fixed supports 25, said shaft 24 being provided with collars 26 pinned thereto and disposed above and below the supports 25 so as to prevent endwise movement of said shaft. The shaft 24 (llI'lVGS a suitable speed responsive device which serves to indicate or establish, by the degree of movement given to a movable part or member, the speed at which the vehicle is traveling. As illustrated, this speed re sponsive device SI comprises a block 27 fixed to the shaft 24, and another block 28 which is loosely mounted on the shaft 24 so as to slide lengthwise thereon. lVeighted balls 29 are connected tothe blocks 27 and 28 by links 30, and a compression spring 31 is interposed between the two blockis 27 and 28. The block 28 is formed with two flanges 32 between which are disposed rollers 33, which are supported by the bifurcated ends of an arm 34 which is pivotally supported on a fixed pin or bearing stud and which has integral therewith a downwardly extending arm 36. The operation of the speed responsive device SI hereinbefore described is similar to that of the well known centrifugal governor and will be readily understood without further explanation;

In addition to the speed responsive device ST, the train control apparatus in cludes means for establishing a predetermined permissive speed for the vehicle at different points in its travel;.and according to the embodiment of the invention illustrated, the predetermined permissive speeds for the vehicle are established by the movement ofa member which is arranged so that it may be connected to the vehicle and be moved gradually in accordance with the distance traveled by said vehicle. In a simplified arrangement of parts shown in the drawing, a beveled gear 37 is fixed to the shaft 24 and meshes with a similar hey-- eled gear 38 fixed to a shaft 39. The shaft 39 is mounted for rotation in suitable supports 40 and is provided with collars 41 ioo which are fastened to said shaft and are shaft. Secured to the shaft 39 is a worm 42 which meshes with a worm gear 43 journaled on a fixed bearing pin or stud 44; and fixed to the gear 43 so as to turn therewith is a smaller gear 45 which meshes with a larger gear 46 journaled on a fixed bearing pin or stud 47. In a similar way intermeshing gears 48, 49, 50, 52 and 54 are journaled on fixed bearing studs 51 and 53 and serve to complete a train of gears which will be recognized as a well known type of reduction gearing. Journaled at one end on the stud 53 is a lever'55 which carries two intermeshing gears 56 and 57, the gear 56 being also in mesh with the gear 52.

Disposed above the outer or free end of the lever 55 is a cam control magnet K comprising two coils 58, the pole pieces of which are connected at their lower ends by the usual yoke 59. The armature 60 of the cam control magnet K is guided by pins 61 fixed in the pole pieces of the coils 58; and this armature 60 is fastened to a rod 62 which extends downward through a guiding opening in the yoke 59 and is pivotally connected to the lever 55. A collar 63 is fastened to the rod 62, and interposed between said collar and the yoke 59 is a compression spring 64 which tends to move the rod 62 and the lever 55 to their upper position, opposite to the position shown in Supported in suitable bearings (not shown) is a cam-shaft 65 to which is fastened a gear 66. The gear 66 is arranged in the same plane as the gear 57 and may be driven thereby at times when the lever 55 is in its upper position. When the gear 57 is in its lower position, as shown in Fig. 1-, and is disconnected from the gear 66, the cam-shaft 65 and its associated parts are free to be turned by a counterweight 67 secured to the gear 66 to a normal or initial position, as shown in Fig. 1, in which the counterweight 67 is directly underneath the axis of the cam-shaft 65. Securely fastened to the cam-shaft 65 is a cam-shaped plate 68. hereinafter termed the cam, and this cam'68 has a predetermined shape for the reasons more fully explained hereinafter. Also securely fastened to the camshaft 65 is a circular plate 69 which is provided with a V-shaped notch 70 in its edge, for the purpose more fully explained hereinafter.

From the construction so far described it can be seen that a movable part, namely, the speed arm 36, is caused to assume different positions in accordance with variations in the actual speed of the vehicle, and that another movable part. namely, the cam 68, is caused to be gradually moved at times in accordance with the distance traveled by the vehicle and may be used to establish a permissive speed for the vehicle at each point in its travel as determined by the shape of said cam. The train control system further includes suitable means for comparing the permissive speed of a vehicle, as established by't'he cam 68, with the actual speed of the vehicle as established by the speed arm 36, and for automatically controlling the movementof the vehicle whenever its actual speed exceeds the limiting permissive speed.

In the construction illustrated, a floating lever 71 is pivotally connected at its lower end to the speed arm 36 and carries at its upper end a freely revoluble roller 72 which bears against the edge of the cam 68. A link 73 is pivotally connected at one end to the floating lever 71 between its ends and at its other end to an arm 74 integral with a contact sector 75 which is mounted for rotation on a suitable pin 76. The edge of the contact sector 75 consists of two concentric portions of different radii which are connected by an inclined portion consituting a shoulder 7 7 the urpose of which will be explained more fuly hereinafter.

Adjacent to the contact sector is a suitable fixed support 78 which carries blocks 79 of suitable insulating material; and connected at one end to said support 78 is a tension spring 80 which is connected at its other end to the arm 74 of the contact sector 75. Secured in the blocks 79 and the support 78 are a plurality of contact supports 81 of the same construction which support contact fingers 82, 83, 84 and 85 and which also serve as binding posts. Each of these contact fingers is supported on its corresponding support in the same manner, and a description of one will suffice for all. Referring to the contact finger 85, its lower end is formed with a pair of ears 86 which are connected by ahorizontal pin 87 to its corresponding support 81, so that the contact finger 85 may rock in a vertical plane. The contact fin r 85 is pressed in one direction, towar d the left, as viewed in Fig. 1, by a compression spring 88.

Fastened to the contact finger 82 is a freely revoluble roller 89 of suitable insulating material which bears against the outer edge of the contact sector 7 5. Normally, when the parts are inthe position shown in Fig. 1, the contact finger 82 is moved some distance to the right from its contact support 81 against the opposition of the spring 88, while the contact finger 83 is moved a shorter distance from its contact support 81 so that, if the contact finger 82 were allowed to move to the left, said contact fingers 82 and 83 would separate since the contact finger 83 would be able to move only a short distance as compared with the distance which the contact finger 82 could move. The contact fingers 84 and 85 are normally separated, as shown in Fig. 1. and are so arranged that when the contact finger 84 is moved to the right, as

viewed in said Fig. 1, it will be brought into electrical contact with the contact finger 85. The contact finger 84 is pivotally connected to a link 90 which extends toward the camshaft and is pivotally connected to an arm 91, which is journaled at its upper end on a fixed pin 92 and which is formed at its lower end with a V-shaped projection adapted to enter the notch in the circular plate 69.

Associated with the train control apparatus hereinbefore described and constituting one of the important parts of the train control system embodying this invention is a protective device or rela P which as shown comprises a solenoi 93 having a core or plunger 94. A contact disk 95 is secured to the plunger 94 but insulated therefrom and is arranged to contact with a pair of contact springs 96 for a portion of the movement of said plunger. Another contact disk 97 is fastened to the plunger 94 and insulated therefrom, but the latter contact disk 97 is arranged so as to break electrical contact with its cooperating springs, indicated as arrows, upon a slight downward movement of the plunger 94 from its upper position shown in Fig. 1. To the lower end of the plunger 94 is fixed a piston 98 having a flexible packing which is disposed in a dash-pot cylinder 99 having a small escape opening-100 in its lower end.

The parts of the protective relay P are shown in Fig. 1 in their normal position corresponding to the energized condition of said relay; and"it can be seen that when the solenoid 93 is deenergized, the plunger 94 commences to move. downward under its own weight gradually at a rate determined by how fast air may escape from the dash-pot cylinder 99 through the small hole 100. During the first part of the downward movement of the plunger 94 the contact disk 97 is moved out of contact with its cooperating contact springs; and after the lapse of a predetermined time for which the relay P is designed, the contact disk 95 will move out of electrical contact with its cooperatingcontact springs 96. Obviously, if the sole noid 93 is reenergized before the plunger 94 completes its downward movement, said plunger will be restored to its upper position, so that the circuit controlled by contact disk 95 and the contact springs 96 will not have been opened.

Associated with the protective relay P are speed contacts 102 and 103 which tend to close but which are separated by a finger 101 secured to the arm-34 when the speed of the vehicle exceeds a predetermined low speed, as for example, 12 miles per hour.

According to the embodiment of the invention illustrated it is contemplated that the speed of the vehicle will be retarded by the well known system of air brakes, and

since this system of brakes is well known to those skilled in the art, it is only necessary to illustrate the manner in which the parts of the train control system act to control this system of air brakes. A portion of the train pipe included in the said system of brakes is shown and designated 104; and connected to said train pipe 104 is a valve 105 of suitable construction having a stem 106 which is controlled by a solenoid 107. As is well understood by those skilled in the art, the venting of the train pipe 104 automatically causes an application of the brakes; and according to the arrangement of parts illustrated, the valve 105 is held closed when the solenoid 107 is energized but is opened by a spring or other means, so as to vent the train pipe 104, when said solenoid is deenergized.

The train control apparatus is governed by a relay CS, hereinafter termed the speed control relay, which comprises two windings 108 and 109 and is provided with two armatures or contact fingers 110 and 111, said armatures being illustrated conventionally. The speed control relay CS is also in turn controlled by another relay GP, hereinafter termed the pick-up relay, which is provided with two contact fingers or armatures 112 and 113 and which is constructed, in a way which will be readily understood by those skilled in the art of railway signaling, so asto be operated only by alternating current.

Referring to Fig. 2 of the accompanying drawing, one track rail 2 of the stretch of track shown in this Fig. 2 is divided by insulating joints 167 in the usual manner into blocks, as A, B and C, the entire-length of the block B only being shown. lhe electrical energy for the trackway circuits shown in Fig. 2 is illustrated as derived from an alternating current generator 168 which is connected to line wires 169 and 170 which extend along the track according to the usual practice. The parts and electrical conductors associated with each block are the same, and for convenience the corresponding parts of the several blocks will be given corresponding reference characters with distinguishing exponents.

Located at one end of each block, preferably the exit end, is a track transformer 171, the primary of which is connected to the line wires 169 and 170, and the secondary of which is connected by conductors 172 and 173 across the track rails 1 and 2 of the corresponding block. At the other end of each block a track relay 174 is connected across the track rails 1 and 2 in the usual manner, each track relay being provided with two armatures or contact fingers 175 and 176 which are illustrated conventionally. Associated with each block is a ramp R, and according to the arrangement of trackway circuits illustrated there is a ramp at the entrance to each block which is so located with reference to the insulating joint 167 that the contact shoe of a vehicle will engage with that ramp for apart of its length before the first pair of wheels and axle of the vehicle pass said insulating joint, and also so that said contact shoe will engage with said ramp after the first pair of wheels and axle of the vehicle have passed said insulating joint. Associated with each ramp is a transformer T, the primary of which is connected across the line wires 169 and 170, and the secondary of which'is adapted to be connected at times across the corresponding ramp R and the track rail 1. The different electrical connections to the secondaries of the transformers T will not be set forth in detail since these electrical connections and the different circuits involved will be more fully explained hereinafter in the description of the operation. In order to illustrate a feature of the present invention, two vehicles, together with the train control apparatus and electrical connections therefor carried by said vehicles, are illustrated in Fig. 2, it being understood that more than two vehicles each equipped with the train control apparatus may be conp ected together in some way as shown in Operation: The parts of the speed control apparatus are shown in Fig. 1 in the position which they assume when said apparatus, except for imposing a limitation upon the maximum speed which the vehicle may attain at any time, as explained hereinafter, is not effective to control the movement of the vehicle.

Disregarding for the present the way in which the parts of the train control apparatus are caused. to assume the position shown in Fig. 1, since this feature of the operation will be pointed out hereinafter, it is considered expedient to trace the different controlling circuits for the different parts prior -to discussing in detail the successive steps in the operation; and in order to facilitate the identification of these circuits, each circuit as it is traced will be given a distin guishing number and will be referred to by that number. \Vhen the parts are in the position shown in Fig. 1, which may be termed the normal position, the speed control relay CS is energized by a circuit which may be traced as follows:

( 'z'rcuz't number one.

Commencing at the battery 200, conductors 114, 115 and 116, contactspring 15, contact piece 16, conductors 117 and 118, armature 110 in its upper position, conductor 119, winding 109 of the CS relay, and conductors 120, 121, 122, 123, 124 and 125 back tothe battery 200.

The speed control relay CS may be energized so that its armatures may be raised to or held in their upper position when the armature 112 of the pick-up relay CP is raised to its upper position, the circuit for energizing said relay CS being traced as follows:

Circuit number two.

' Commencing at the battery 200, conductors 114, 126 and 127, armature 112 in its uper position, conductors 128 and 129, winding 108 of the CS relay, and conductors 130, 121, 122, 123, 124, and 125 back to the battery 200. One terminal of the winding of the GP relay is connected by conductor 133. to the contact shoe 11, and the other terminal of said winding is connected by conductors 134, 122, 135 and 136 to the axle 5 or frame of the vehicle. The pick-up relay CP is controlled by the difference of potential existing between a ramp R and a track rail in the man- Circuit number three. Commencing at the battery 200, conductors 114, 126 and 137, armature 111 1n 1ts upper position, conductor 138, coils 58, and conductors 139, 135, 122, 123, 124, and 125 back to the battery 200.

The solenoid 107 controlling the valve 105 may be energized by either of two circuits having several parts in common. The first circuit for energizing the solenoid 107 may be traced as follows:

'( ircu'it number four.

Commencing at the battery 200, conductors 114, 115 and 140, contact fingers 83 'and 82, conductors 141 and 142, contact springs 96 and contact disk 95. conductors 143 and 144, solenoid 107, and conductors 145. 124. and 125 back to the battery 200.

The other circuit for energizing the solenoid 107 may be traced as follows:

(*ircuit number five.

Circuit number aim.

Commencing at the battery 200, conductors 114, 115 and 116, contact sprlng 15, contact piece 16, conductors 117' and 148,

("i r014 it number seven.

Commencing at the battery 200, con-- ductors 114, 126, 127 and 153, armature 113 in its upper position, conductors 154 and 151, solenoid 93, and conductors 152 and 125 back to the battery 200.

The solenoid 93 may also be energized by a circuit which may be traced as follows:

Circuit number eight.

Commencing at the battery 200, couductors 114, 126 and 137, armature 111 of the relay CS in its lower position, conconductor 155, contact fingers 84 and 85 closed, conductors 156, 150 and 151, solenoid 93, and conductors 152 and 125 back to the battery 200.

Assuming the parts of the train control apparatus to be in the normal position shown in Fig. 1, they will remain in this position until the vehicle passes a ramp R, whereupon said parts will remain in their normal position or will be changed so as to initiate the operation of the train control apparatus depending upon whether or not a difference of potential exists between said ramp and a track rail; and to explain fully the operationofthe train control ap paratus it will be necessary to assume different trafiic conditions along the stretch of track shown in Fig. 2 and explain the controlling effect produced on the train 'control apparatus by these different conditions.

For the present, the control of the train control apparatus on only one vehicle will be considered, and the features of the operation of the system involved when there is more than one vehicle equipped with the train control apparatus included in a train will be pointed out hereinafter.

For the first tratiic condition to be considered assume that the vehicle under consideration is in the block A and about to enter the block B; that this vehicle has heretofore found the track unobstructed and is proceeding with the parts of its train control apparatus in'the normal condition. as shown in Fig. 1, and that neither the block B nor the block C is occupied by another train. When the contact shoe 11 of the vehicle engages the ramp R, said contact shoe is raised and also establishes electrical connection with said ramp. The raising of the contact shoe 11 moves the contact spring 15 out of contact with the contact piece 16, thereby interrupting the circuit number one for normally energizing the speed control relay CS and also interrupting the stick circuit number six for energizing the solenoid 93 of the protective relay P. Under the conditions assumed, with no. train in the block B, the track relay 174 is energized and its armatures are in the upper position, so that high voltage is applied to the ramp R; and with this high voltage, the armatures of the'pickup relay GP are raised by current flowing in a circuit which may be traced as follows: Commencing at the ramp R, contact shoe 11, conductor 133, relay (.P. conductors 134. 122, 135, and 136, through the wheels and axles of the vehicle to the track rail laconductor 179, secondary of the transformer T, conductor 17 8, armature 175 in its upper position, and conductor 177 back to the ramp R. The raisingof the armature 112 of the pick-up relay GP establishes the circuit number two for energizing the winding 108 of the speed control relay CS, so that the armatures of this relay are held in their up per position. The raising of the armature 113 of the pick-up relay CP'establishes a circuit number seven for energizing the solenoid 93 of the protective relay P so that in spite of the fact that circuit number six for energizing said solenoid is broken by the lifting of the contact shoe 11, said solenoid is immediately thereafter energized and restores the plunger 94 to its upper position before sumcient time has elapsed tomove the contact disk 95 out of contact with the contact springs 96.

As the vehicle under consideration progresses and its first pair of wheels and axle enter the block B, the track relay 174 of said block. is shunted and its armatures are caused to assume their lower position. as will be clearly understood by those skilled in the art of railway signaling. The dropping of the armature 175 of the track relay 174 interrupts the circuit last traced by means of which current for energizing the pick-up relay (P is supplied from the transformer T; but with tratiic conditions as assumed another circuit for supplying voltage to the ramp R is established. so that current may be supplied to the pick-up relay (P along a circuit which may be traced as follows Commencing at the ramp R. conductor 177, armature 175 in its lower position, conductor 180. armature 176 in its upper position, conductor 181. intermediate tap of the secondary of the transformer T conductor 179 to the track rail 1, through the wheels and axles of the vehicle, thence along conductors 136, 135, 122 and 134 to the rc av (1 through the relay CP, conductor 1333, contact shoe 11, and back to the ramp R.

It can be seen that the circuit last traced applies only low voltage to the ramp R: and the pick-up relay CP is suitably constructed so that this low voltage will not cause sutiicient current to flow through said relay to raise its armatures from their lower position but will. however, be sutlicient to hold the armatures of said relay in their upper position if they are already there. The pick-up relay (1 may be made selectively responsive to ditl'erent voltages in different ways. as for example as shown in my prior application Serial No. 2559. filed January 16, 1915. In this way. when the vehicle passes a ramp to which high voltage is applied. and this high voltage is subsequently changed to low voltage. the armatures of the pick-up relay (P will be first raised and then will be held in the raised position until the contact shoe 11 leaves engagement with this ramp; and when said contact shoe leaves engagement with said ramp. the circuit number one for normally maintaining the speed control relay CS energized is closed before the supply of current to the pick-up relay 'CP is interrupted andits armatures drop. So long as the armature 113 of the pick-up relay CP is in its upper position the solenoid 93 of the protective relay P is energized by current flowing along circuit number seven. and the stick or maintaining circuit number six for the solenoid 93 of the pick-up relay CP is established when the contact shoe 11 leaves engagement with the ramp before the circuit number eight is interrupted. so that under these conditions the protective relay P is held in its normal position.

For the next trafiic condition to be considered assume that the vehicle in questionis in the block A and about to enter the block B; that this vehicle has heretofore found the trackway unobstructed and is proceeding with the parts of its train control apparatus in the normal condition, as shown in Fig. 1.-and that. while the block B is not occupied by another train, the block C is occupied. lVhen the contact s'hoe l1 first engages the ramp R at the entrance to the blockB the same operation of parts occurs as previously described until the first pair of wheels and axle of the vehicle in question enter the block B and cause the dropping of the 'armatures of the track relay 174. Since the block C is assumed to be occupied by another train the track relay 174 of this block is shunted and its armature 176 is in its lower position sothat the circuit hereinbefore traced for supplying low voltage to the ramp R after the wheels and axle of the vehicle enter the block B is inrelay CS opens another break in the circuit number one, so that after the shoe 11 leaves engagement with the ramp R and permits the contact spring 15 to again touch the contact piece 16, nevertheless, the circuit number one will not be established. The dropping of the armature 111 of the speed control relay CS interrupts the circuit number three-for normally energizing the cam control magnet K, and consequently the lever 55 and the gears 57 and 56 carried thereby are moved to their upper position, opposite to that shown in Fig. 1, by the spring 64, so that the gear 57 is brought into mesh with the gear 66, thereby operatively connecting the cam-shaft 65 to the wheels of the vehicle, so that as the vehicle travels the cam-shaft 65 is gradually turned, in one direction or the other depending upon which way the vehicle is headed and upon which direction it is traveling, exactly in correspondence with the distance traveled by the vehicle. Upon the first movement of the cam-shaft '65 the circular plate 69 is moved so as to swing the arm 91 to the right, thereby forcing the contact finger 84 into contact with the contact finger 85; and since the armature 111 is in its lower position, the circuit number eight for energizing the solenoid 93 is established. The time required for the plunger 94 of the protective relay P to move from its upper position, shown in Fig. 1. to its lowerposition where the contact disk 95 is out of contact with the contact springs 96 is so determined and 100 adjusted as to be slightly greater than the time required'tor the armature of the relay CS to drop. the cam control magnet K to be deenergized. the arm 55 and the gears carried thereby to be moved to their-upper position and the cam shaft 55 turned sufficiently to close the contact fingers 84 and 85 after the supply of current to the windings of the relay CS is first interrupted. In practice it is found that there must be a very small angular movement of the camshaft 65 for a considerable distance traveled by the vehicle. as, for example, one degree for each ten feet. and mechanical construction makes it necessary for positive action that the cam-shaft 65 should move through a considerable angle before the contact fingers 84 and 85 are closed. In other words. in practice, the contact fingers 84 and 85 are not closed until the train has traveled considerable distance. as for instance 30 feet; and since the time required for the train to travel this distance depends upon its speed. in some cases where the speed of the vehicle is very low. the time required for the vehicle to travel this certain distance would be so great that the contact fingers 84 and 85 will not be closed to establisli the circuit number eight before the time for which the protective relay P is set had elapsed. For this reason the speed contacts 102 and 103 are provided, so that below a certain low speed, as for example 12 miles per hour, these contacts will be closed and will establish a shunt for the contact springs 96 and the contact disk 95, so that although the circuit number eight is not established subsequent to the circuit number six within the time limit for which the protective relay P is set, the solenoid 107 controlling the brakes of the vehicle will be maintained energized by the circuit number five.

With the cam-shaft 65 connected to the wheels of the vehicle and gradually turned as the vehicle travels, there commences a gradual reduction in the permissive speed for the vehicle, and unless the actual speed of the vehicle is kept less than the permissive speed an automatic application of the brakes results. With the particular arrangement of parts shown in Fig. l this is accomplished by the cooperation of the speed responsive device SI and the cam 68. In general, the shape of the cam 68 is determined with reference to the gradual decrease in permissive speed desired, and in practice this gradual decrease in permissive speeds is preferably determined from the braking curve of the vehicle with which the cam 68 is associated. Without entering into any detailed description of the factors determining the shape of the cam 68, since this forms no part of the present invention, the radii of the cam 68 correspond to speed and the angular displacement of the cam from its initial position shown in Fig. 1 corresponds to distance traveled by the vehicle. The shape of the cam 68 shown in Fig. 1 is in general the shape of a practical cam for controlling the speed of a railway vehicle, although no attempt has been made to show the precise shape of this cam, and it can be seen that as the cam 68 is turned its radii increase and cause a movement of the upper end of the floating lever 71 to the left, as viewed in Fig. 1. The speed responsive device SI governs the position of the speed arm 36 and the lower end of the floating lever 71 and causes the lower end of said floating lever to assume positions more and more to the left of that shown in Fig. 1 as the actual speed of the vehicle is greater. With the cam 68 in its initial position shown in Fig. 1 it can be seen that the lower end of the floating lever 71 may be moved to the left, corresponding to higher speeds, for a considerable distance before the contact sector 75 is rocked far enough to bring the shoulder 7 7 at its edge ascent/e quent automatic application of the brakes. In this way there is established a limitation upon the maximum speed at which the vehicle may travel at any time when the cam 68 is stationary. As the cam 68 is gradually turned, the upper end of the floating lever 71 is moved more and more to the left, so that the lower endof said floating lever cannot be moved as far to the left, corresponding to higher speeds, without moving the contact sector 75 to bring the shoulder 77 at its edge opposite to the roller 89. In other words, as the cam 68 turns it imposes a gradually decreasing limitation upon the actual speed at which the vehicle may travel and this limitation upon the permissive speed is so se lected that the vehicle will be brought to a stop or to a predetermined low speed when it reachesthe end of the block B.

For the next tratfic condition to be considered assume that the vehicle, having had its speed controlled while passing through the block B in a manner described, reaches the end of the block B, and further assume that the train assumed to occupy the block (3 still occupies the block C. When the contact shoe 11 of the following vehicle engages the ramp R the armatures of the pick-up .relay CF will not be raised, since the circuit analogous to the circuithereinbefore considered in connection with the ramp R by means of which high voltage is applied to the ramp R is interrupted at the armature 17 5 of the track relay 174 and either a low voltage or zero voltage is applied to the ramp R depending upon whether or not the next block in advance of the block C is occupied. Consequently, the speed control relay CS remains deenergized and the vehicle remains under the control of its train control apparatus, and if the vehicle proceeds it must do so under the restrictions imposed by its train control apparatus.

For the next traffic condition assume that by the time the vehicle in question, which has had its speed controlled while passing through the block B, reaches the end of the block B. the train formerly occupying the block C has moved out of that block into the next block in advance. With these traflic conditions the track relay 174 of the block C is energized, so that high voltage is applied to the ramp R and when the contact shoe 11 of the following vehicle engages theramp R the pick-up relay CP is energized suflitures. The raising of the armature 112 of the pick up relay GP establishes circuit number two which energizes the winding 108 of the speed control relay CS and raises the armatures of said relay CS. The raising of the armature 110 prepares the circuit number one for normally energizing the speed-control relay CS so that a subsequent closing of the contact spring 15 with the contact piece 16 will establish this circuit. The raising of the armature 111 interrupts the circuit number eight, but since circuit number seven is already established because the armature 113 of the pick-up relay CP is in its upper position, the protective relay P remains energized. The raising of the armature 111 also reestablishes the circuit number three for energizing the cam control magnet K, so that the armature 60 of said cam control magnet is attracted and the lever 55 moved to its lower position as shown in Fig. 1 so as to disconnect the gear 66 from the gear 57, whereupon the counterweight 67 returns the cam-shaft 65, the cam 68 and the circular plate 69 carried thereby to the normal or initial position shown in Fig. 1. In this way, the parts of the train control apparatus on the vehicle, after having passed through the cycle of operation, are restored to their normal position ready for the next operation. With a train in the block next in advance of the block C this next operation will occur as soon as the pair of wheels and axle of the vehicle in question enters the block C, for the same reasons and in the same way as hereinbefore explained when the vehicle entered the block B while the block C was occupied by another train.

Referring now to the case where two or more vehicles, each equipped with the train control apparatus illustrated in Fig. 1, are included in the same train, it can be seen from the previous explanation that the train control apparatus on these several vehicles are successively set into operation as they pass a ramp, as the ramp R, to which only zero voltage is applied, due to the presence of another train in the second block in advance, as the block C. Consequently, as the train including the several vehicles reaches the end of the block B, it becomes desirable to simultaneously restore the train control apparatus on these several vehicles to their normal initial position, providing trafiic conditions permit, in order that the train control apparatus on a rear vehicle will not compel the train as a whole to travel at a restricted speed by the ramp R until this rear vehicle has reached the ramp R since such a delay in the restoring of. thetrain control apparatus on a rear vehicle to its normal or initial position would cause an unnecessary and objectionable delay of the entire train. An arrangement of controlling circuits for causing simultaneous energization of the speed control relays CS on the several vehicles is illustrated in Fig. 2; and in this arrangement a continuous conductor or bus line 132 extends throughout the length of the train and this bus line 132 is connected by a conductor 131 on each vehicle with the conductor 128. By reason of this arrangement of circuits when the pick-up relay CP on the front car of the train is energized sufliciently to raise its armatures, at the same time that current is supplied to the winding 108 of the speed control relay CS on that particular vehicle, current is supplied along conductor 128 and 131 to the bus line 132 and thence through the windings 108 of the speed control relays CS on the several vehicles. For example, when the armature 112 of the pick-up relay OP on the forward car shown in Fig. 2 is raised, the winding 108 of the relay CS on the rear car is energized by current flowing in a circuit which may be traced as follows: Com mencing at the battery 200 conductors 11 1 126 and 127 armature 112* in its upper position, conductors 128 and 131 to the bus line 132, thence to the rear car, then along conductors 131 and 129, winding 108 of the speed control relay CS on the rear car, conductors 130, 121, 135 and 136 through the wheels-and axles of the rear vehicle to the track rail 1, through the wheels and axles of the front vehicle, conductors 136 135 122 123 124 and 125 back to the battery 200 The protective relay P and its associated parts and controlling circuits are combined with the train control apparatus operating as hereinbefore described so as to afford a check on the operation of certain parts of this apparatus; and referring to the manner in which this check is accomplished, it can be seen that the solenoid 93 of the protective relay P is deenergized each time the vehicle passes a ramp by the lifting of the contact shoe 11 and the interruption of circuit numher six, and that after a lapse of a certain time following the engagement of the contact shoe 11 with a ramp, the contact disk 95 of said protective relay would, unless the solenoid 93 of said protective relay is energized by the closing of either the circuit number seven or the circuit number eight, reach its lower position in which the circuit number four for energizing the brake controlling solenoid 107 is broken,,thereby resulting in the automatic application of the brakes, unless the speed of the vehicle at the time is low enough to permit the speed contacts 102 and 103 to be closed, so that the circuit number five for energizing the brake ber seven by the raising of the armature 113 of the pick-up relay UP, and this occurs if the ramp which the vehicle passes has high voltage applied thereto and this high voltage is followed by low voltage. In this way the protective relay is prevented from causing an automatic application of the brakes when the vehicle passes a ramp at a time when traliic conditions are such as to permit the train to proceed at any speed less than the limiting maximum speed hereinbetore explained, so that provision is made for permitting the vehicle to continue its travel under proceed conditions without being stopped. Another thing which may occur and prevent the continued action of the pro-e tective relay P and the resultantapplication of the brakes is the closing of circuit number eight. This circuit is not closed unless the,

armatures ot' the speed control relay CS drop, as they properly should, and unless the cam control magnet K becomes deenergized,

the lever moved so as'to bring the gear 5? into mesh with the gear 66, and the gearing for driving the cam-shaft 65 is operating properly, so that the circular plate 69 is moved so as to close the contact fingers 84 and 85. In other words, the protective relay P acts to check the dropping of the armatures of the speed control relay CS and the initial movement of the cam-shaft 65. The

am-shaft should commence to move when a train enters a block, as the block B, while another train occupies the next block in advance, as the block C; and the system embodying this invention assures that this movement of the cam-shaft shall occur unde i;

these tratiic conditions, or else the failure will be immediately manifested by an automatic application of the brakes or in some other suitable manner. Tracing the respective controls of the several parts leading to the result desired, namely the movement of the cam-shaft 65, it can be seen that the camshaft 65 should commence to move when the speed control relay CS is deenergized, and

said relay CS should he deenergized when the contact shoe 11 is engaged b a ramp-to which no voltage is applied. W ien the contact shoe 11 engages such a ramp the action of the protective relay P is initiated, and

unless the speed control relay CS drops, as

it should. and unless actual movement of the cam-shaft (35 occurs so as to cause the closing ct the contact fingers 84 and 85, the action of the protective relay P continues and after the lapse of a certain time causes an automatic application of the brakes which manitests immediately that there is some defect in the chain of apparatus WllCll should cause the cam shaft to move.

Another possible failure or detect against which the protective relay l affords protecac tion is that where for some reason current is improperly applied to the bus line 132 so as to cause an energization of the windings 108 ot the speed control relays CS on the several vehicles of the train regardless of whether 65 or not it is proper for these windings to be energized. As one illustration of the Way in which current may be improperly applied to the bus line 132, suppose that the termi-. nals of the several batteries 200 carried by the vehicles in the train are connected by conductors 11st and 201 to a train battery bus 202, such an arrangement being desirable in case several vehicles, each provided with a local battery, are connected together in a train. Vith such an arrangement of a train battery bus 202 as well as the automatic reset bus 132 extending through the train, it can be seen that a cross or improper electrical connection between these two bus lines 202 and 132 would cause an improper energization of the windings 108 of the speed control relays CS on the several vehicles, this improper energization of said windings 108 producing a dangerous condition in that the armatures ot' the speed control relay CS would not drop and commence the operation of the train control apparatus when it is proper that they should do so. The use of the protective relay P, however, prevents such a dangerous condition from resulting from such a cross between the bus lines 202 and 132, because as each vehicle passes a ramp, and this ramp has zero voltage applied thereto so that the armatures of the pick-up relay Cl are not raised, the protective relay P will continue in operation and in time will cause an automatic application of the brakes in spite of the fact that the improper cross prevents the .dropping ot' the armatures of the speed control relay CS, that is, the circuit number six for maintaining the solenoid 93 of the protective relay P is broken when the contact shoe 11 of the vehicle engages the ramp, and said solenoid 98 is not energized either by circuit number seven, which is broken at the armature 113 of the pick-up relay GP, or by the circuit number eight which is broken at the armature 111 of the speed control relay CS.

' This application is a continuation of my no prior application Serial No. 2,868, filed January 18, 1915, so far as the subject matter common to both is concerned.

Althoughl have particularly described the construction of one physical embodiment 115 of my invention, and explained the operation and principle thereof; nevertheless. I desire to have it understood that the form selected is merely illustrative, but does not exhaust the possible physical embodiments of the idea of means underlying my inven tion. Various modifications and substitutions may be made in the particular embodiment of my invention shown and described without departing from my invention, since the function and operation of the parts constituting my invention, particularly the protive' device, may be fully carried out with forms and types ot associated parts other than those shown and described. The means 139 for establishing communication between the vehicle or train and. the track, the apparatus automatically controlling the movement of the vehicle or train, and the other associated controlling devices and circuits may be varied without departing from my invention, and it should be understood that the expressions and terms used in the appended claims are intended to include the various modifications and substitutes which may be used in connection with this invention in place of the particular parts and circuits shown and described.

What I claim as new and desire to secure by Letters Patent of the United States, is:

1. In an automatic train control system,

in combination: a vehicle and a track there-' for; train control apparatus on the vehicle; impulse devices located at intervals along the track and automatically controlled in accordance with traflic conditions ahead for governing the operation of said apparatus; and a protective device operated when said apparatusfails to respond to the governing influence of said impulse devices.

2. In an automatic train control system, in combination: a vehicle and a track therefor; train control apparatus on the vehicle; means for automatically controlling said apparatus at different points along the track in accordance with traflic conditions ahead; and a protective device governed by said apparatusand said means and operated when said apparatus fails to respond to the control of said means within a predetermined time.

3. In an automatic train control system, in combination: a vehicle and a track therefor; impulse devices located at intervals along the track and automatically controlled in accordance with traflic conditions; train control apparatus on the vehicle governed by said impulse devices; a circuit on the vehicle; means controlled by said impulse devices and'tending to govern said circuit after the lapse of a predetermined time following its control by saidimpulse devices; and means rendered active when said apparatus is o erating for preventing the op'rationof sai means.

at. In an automatic train control system, in combination: a vehicle; train control apparatus on the vehicle; a time controlled protective device set into operation at intervals during the travel of the vehicle; and means rendered active when said train control apparatus is operated for preventing the operation of said protective device.

5. In an automatic train control system in coinbination: a vehicle and a track therefor; ramps located at intervals along the track; traflic controlled means for govern- 'ing the electrical condition of said ramps;

a contact shoe carried by the vehicle and adapted to engage said ramps; electrically operable means for governing said train control apparatus in accordance with the electrical condition of said ramps; a time controlled protective device set into operation when said contact shoe engages aramp in the danger controlling condition; and means for preventing the operation of said protective device when said train control apparatus responds to the controlling influence of said electrically operable means. I

6. In an automatic train control system, in combination: a vehicle and a track there for; automatic train control apparatus on the vehicle including a member adapted to be connected to the wheels of the vehicle and gradually moved in accordance with the distance traveled thereby; traffic controlled impulse devices located at intervals along the track for governing said apparatus; a protective device set into operation each time the vehicle passes one of said impulse devices in the danger controlling condition; and means for preventing the operation ofsaid protective device when said member has commenced its movement.

7. In an automatic train control system, in combination: a vehicle and a track therefor divided into track circuit blocks; an impulse device associated with each block and governed by the next block in advance; train control apparatus on the vehicle for compelling a reduction in speed following its initial operation; means controlled by said Impulse devices for governing the operation of said apparatus; mechanism for retarding the movement of the Vehicle; and checking means set into operation each time the vehicle passes one of said impulse devices in the danger controlling condition and tending to operate said mechanism after the lapse of a predetermined time, Said checking means being governed by said train control apparatus and being rendered ineffective upon the initial operatlon of said apparatus.

8. In an automatic train control system, in combination: a plurality of vehicles and a track therefor; train control apparatus on each vehicle; a circuit for governing the train control apparatus on the several vehi;

'cles simultaneously; means for supplying current to said circuit; trafiic controlled impulse devlces located at intervals along the track for "governing said meansand said train control apparatus; and a protective de- 1 vice on each vehicle set into operation when the train control apparatus thereon fails to respond to the governing influence of said impulse devices.

9. In an automatic train control system, in combination: a plurality of vehicles and a track therefor; train control apparatus on each vehicle; traffic controlled impulse devices alon the track; means governed by said impu se devices for controlling said train control apparatus so as to initiate the operation thereof; means overned by said impulse devices for causing simultaneous restoration of said train control apparatus on the several vehicles; and a protective device governed by both of said means and tending to operate when both fail to respond to the governing influence of said impulse devices.

10. lln an automatic train control system, in combination: a plurality ofvehicles and a track therefor; train control apparatus on each vehicle; controlling means for simul taneously restoring the train control apparatus on the several vehicles to the initial condition and for maintainin them in their initial condition if then in tiat condition; traffic controlled impulse devices located along the track and always tending to initiate the operation of said train control apparatus and at times when in the proceed condition causing said controlling means to be effective; and a protective device operated when said impulse devices in the caution condition fail to initiate the operation of said train control apparatus.

11. lln an automatic train control system, the combination with a vehicle, of automatic train control apparatus thereon, a control relay on the vehicle for governing said apparatus, a protective device adapted to assume a final active condition after an interval of delay, means governed by said control relay when active to cause operation of the.

train control apparatus, said train control apparatus after commencing its operation acting to restore said protective device to its initial inactive eendition, and impulse transmitting means controlled automatically in accordance with trailic conditions for simultaneously governing said control relay and said protective device in the same way.

12. lln an automatic train control system, the combination with a vehicle, of automatic train control apparatus thereon, a normally energized control relay for overning said apparatus, a protective device tending to assume an active controlling condition after an interval of delay, means dependent upon the control relay being deenergized for restoring said protective device to its inactive condition, and impulse transmitting means governed automatically in accordance with tratlic conditions for simultaneously controlling the control relay and the protective device in the same way.

13. in an automatic train control system, the combination with a vehicle, of automatic train control apparatus thereon, means partly on the vehicle and partly along the track and governed automatically in lac-v *cordance with traiiic conditions ahead for erned automatically in accordance with traffic conditions ahead for influencing said control devices to cause operation of said apparatus under dangerous trafiic conditions, and a protective device subjected to the same controlling influence as said control devices and acting automatic-ally when either said control devices or said train control apparatus fails to respond, the action of said protective device being delayed sufiiciently to permit the control devices and the train control apparatus to respond if operating properly.

15. ln an automatic train control system, the combination with a vehicle, of automatic train control apparatus thereon, a control relay for governing the operation of said apparatus, a protective device adapted to cause an automatic application of the brakes after an interval ot' delay, means governed by said control relay for preventing said protective device from causing an automatic application of the brakes and means partly on the vehicle and partly along the track for governing said control relay and said protective device simultaneously in the same way in accordance with trafic conditions.

16. In an automatic train control system, the combination with a vehicle, of a normally energized control relay thereon, a protective device adapted to change slowly from an initial conditionto an ultimate active condition, means partly on' the vehicle and partly along the track and governed automatically in accordance with traffic conditions for deenergizing said relay and also for setting the said protective device into operation when dangerous tratfic conditions exist, and means eilective only when said control relay isdeenergized for restoring said protective device to its initial condition and for maintaining it in that condition.

17. in an automatic train control system; the combination with a vehicle, of automatic train control apparatus thereon, a control relay for governing the operation of said apparatus, a time controlled protective device adopted to assume an active condition after the lapse of an interval of time, impulse transmitting means partly on the vehicle and part1 along the track and governed an tomaticall y in accordance with traflic conditions ahead for governing said control relay and protective device simultaneously in the same way, and means rendered effective when the control relay is active to cause operation of the train control apparatus and said apparatus has responded. for restoring the protective device to its normal condition.

18. In an automatic train control system. the combination with a vehicle, of automatic train control apparatus thereon, impulse transmitting means partly on the vehicle and partly along the track tending to cause operation of said apparatus at control points along the track irrespective of traflic conditions ahead, said means being also governed automatically in accordance with traflic conditions ahead to transmit to the vehicle a proceed impulse when the trafiic conditions are safe, said train control apparatus being influenced by such proceed impulses to assume its inactive controlling condition, and a protective device on the vehicle subjected to the same controlling influence as said apparatus and acting automatically when said apparatus fails to respond under dangerous traific conditions.

19. In an-automatic train control system, the combination with a vehicle, of automatic train control apparatus thereon, a normally energized control relay adapted when deenergized to set said train control apparatus into operation, impulse transmitting means partlyon the vehicle and partly along the track always tending to cause deenergization of said relay at control points along the track, said means being automatically governed in accordance with traffic conditions and being adapted to transmit a proceed impulse to the vehicle when traffic conditions ahead are safe. said relay being caused to be energized by such proceed impulses, and a slow acting protective device on the vehicle subjected to the same controlling influence as the control relay and adapted to assume an active condition after an interval of delay, said protective device being automatically restored to its inactive condition when the control relay is deenergized and said train control apparatus is operating.

20. In an automatic train control system, the combination with a vehicle. of it normally energized control relay thereon. means partly on the vehicle and partly on the track and governed automatically in accordance with traflic conditions ahead for causing decnergization of said relay under dangerous tratlic conditions, and a protective device governed by said control relay in its deeuergized conditionand also by said means, said protective device being set int-o opera tion by said means at the same time that the control relay is deenergizetl and acting automatically to check the deenergization of said control relay.

21. In an automatic train control system, the combination with a vehicle. of normally inactive train control apparatus thereon. control devices on the vehicle for governing the operation of said apparatus, means partly on the vehicle and partly along the track and governed automatically in accordance with tratfic conditions ahead for influencing said control devices to cause said apparatus to assume an active condition, and a protective device acting when either said control devices or said apparatus fails to respond to the influence of said means.

22. In an automatic train control system, the combination with a vehicle, of a control relay thereon provided with a stick circuit and an energizing circuit, means for controlling said circuits to cause energization or deenergization of said relay in accordance with trafiic conditions, a normally energized protective device tending to assume an ac-- tive controlling condition after an interval of-delay and subjected to the same controlling influence as the control relay, and means responding to the deenergization of the control relay for preventing the protective device from attaining its active controlling condition;

23. In an automatic train control system. the combination with a vehicle, of a normally energized control relay on the vehicle, an electrically operable protective device on the vehicle adapted when deenergized to assume an active condition after'an interval of delay, control circuits for the relay and said device, and an independent energizing circuit for the protective device including a back contact of the control relay, and means partly on the vehicle and along the track for simultaneously governing said control circuits at control points alon the track in accordance with traffic conditions ahead.

24. In an automatic train control system, the combination with a vehicle, of automatic train control apparatus thereon comprising a permissive. speed element adapted to change gradually during the progress of the vehicle to impose decreasing permissive speeds, a protective device adapted to cause automatic application'of the brakes after an interval of delay. means partly 'on the vehicle and partly along the track for initiating the change of said permissive speed element and said protective device simultaneously under dangerous traflic conditions. and means responding to an initial change of said permissive speed device for restoring the protective device to its initial inactive condition. I

25. In an automatic train control system, the combination with a vehicle, of automatic train control apparatus thereon comprising a permissive speed element adapted to change gradually during the progress of the vehicle to impose decreasing permissive speeds. control devices on the vehicle for governing the permissive speed element, a

protective device adapted when set in operation to cause an automatic application of the brakes after an interval of delay, means partly on the vehicle and partly along the track for governing the operation of the control devices and the protective device simultaneously, said means acting under dangerous tratlic conditions to influence said control devices to cause the permissive speed element to change and also to initiate the operation of the protective device, and means responding separately to the initial change of the permissive speed element and the influenced operation of said control devices for restoring the protective device to its initial condition, whereby a failure of the control devices or the permissive speed element to operate properly under dangerous traffic conditions will be automatically detected.

26. In an automatic train control system, the combination with a vehicle and a track therefor divided into blocks, of automatic train control apparatus on the vehicle comprising a permissive speed element adapted to change gradually during the progress of the vehicle through a block to impose decreasing permissive speeds, impulse transmitting means including a control relay on the vehicle for governing the operation of said permissive speed element in each block in accordance with traffic conditions in the next block in advance, and a protective device set into. operation by said impulse transmitting means independently of said control relay when dangerous trattic conditions exist, said protective device being adapted to assume an active condition after the vehicle has traveled partway into the block unless the permissive speed-element has commenced to change.

27. lin an automatic train control system, the combination with a vehicle and a track therefor divided into blocks each provided 'with a normally closed track circuit, of automatic train control apparatus on the vehicle, impulse transmitting means comprising an element associated with each block and cooperating with an element on the vehicle for communicating controlling influences from the track to the apparatus on the vehicle corresponding to the condition of the track circuit of the non block in advance. and a protective device responding directly to the influence of said impulse transmitting means for detecting a failure of the train control apparatus to respond to the controlling influence communicated under dangerous trattic conditions.

28. In an automatic train control system. the combination with a vehicle and a track therefor divided into blocks each provided with a normally closed track circuit, of antomatic train control apparatus on the v hicle, controlling devices for governing the operation of said apparatus, impulse transmitting means comprising an element associated with each block cooperating with an element on the vehicle for communicating controlling influences from the track to the controlling devices on the vehicle in accordance with the condition of the track circuit ot'a block in advance, and a protective device for detecting a failure of the controlling devices or the train control apparatus to respond to such controlling influences communicated under dangerous traitic conditions.

251-111 an automatic train control system, the combination with a vehicle and a track therefor divided into blocks each provided with a normally closed track circuit, of automatic train control apparatus on the vehicle acting to automatically enforce restrictions upon the speed of the vehicle, impulse transmitting means comprising an element associated with each block cooperating with an element on the vehicle for communicating either proceed or caution controlling influences from the track to the vehicle in accordance with the condition of the track circuit of a block in advance, a protective device governed directly by said controlling influences and tending to cause an automatic application of the brakes after a limited travel of the vehicle when a caution influence is received, and means acting when said train control apparatus is operating for preventing an application of the brakes by said protective device.

30. In an automatic train control system, the combination with a vehicle and atrack therefor divided into blocks each provided with a normally closed track circuit. of antomatic train controlling means adapted when conditioned for operation to automatically eni'orce restrictions upon the speed of the vehicle during its progress through a block, impulse transmitting means for causing the said train controlling means to be conditioned for operation when dangerous tratlic conditions exist in a block ahead, and

a protective device controlled by said impulse transmitting means and acting to detect a failure of said train controlling means to respond.

31. in an automatic train control system. the combination with a vehicle and a track therefor divided into blocks. of time-controlled mechanism on the vehicle tending to cause an automatic application of its brakes after the lapse of an interval of time, impulse transmittingg' means partly on the vehicle and partly on the track and governed automatically in accordance with traffic conditions for transmitting to the vehicle a proceed impulse in each block when safe traliic conditions exist in the next block in advance, said impulse transmitting means acting automatically to initiate the operation of said time-controlled mechanism in each block regardless of trafiic conditions ahead, and means on the vehicle responding to said proceed impulses for restoring said mechanism to its initial condition.

32. In an automatic train control system, the combination with a vehicle and a track therefor divided into blocks, of a time-controlled device on'the vehicle adapted to cause an automatic application of the brakes after the lapse of an interval of time, means responsive to the speed of the vehicle and acting to prevent such an application of the brakes by said device when the speed of the vehicle is below a predetermined speed, and

means partly on the vehicle and partly along the track for setting the said device into operation in each block when dangerous traflic conditions exist ahead.

33. In an automatic train control system,

the combination with a vehicle, of a time controlled device thereon adapted to be restored to and maintained in its initial condition by electrical energy, a stick circuit for normally maintaining said device in its'initial condition, an energizingcircuit for restoring said device to or maintaining it in its initial condition independently of its stick circuit, and means partly on the vehicle and partly along the track always interrupting said stick circuit at control points along the track, and at times also causing the said energizing circuit to be established when safe traflic conditions exist ahead.

34. In an automatic train control system, the combination with a train including a plurality of vehicles each carrying automatic train control ap )aratus, of a control relay on each vehicle or governing the operation of its corresponding train control apparatus, a circuit connecting said control relays for simultaneous, operation, impulse transmitting means partly on the vehicle and partly along the track and governed automatically in accordance with trafiic conditions for controlling said relays, and a protective device rendered active whenever acontrol relay fails to respond .to the controlling influences of said impulse transmitting means under dangerous traflic conditions.

35. In an automatic train control system, the combination with a train including .1. plurality of vehicles each equipped with automatic train control apparatus, of a control relay on each vehicle for governing the operation of its corresponding apparatus, a circuit and a source of current on the train for simultaneously energizing said relays, impulse transmitting means governed automatically in accordance with traffic condi-' tions for causing deenergization of said relays under dangerous trafiie conditions and? for establishing a connection between said circuit and said source to energize the several relays when safe traffic conditions exist, and a protective device associated with each control relay and rendered active when that relay fails to become deenergized in response to said impulse transmitting means.

36. In an automatic train control system, the combination with a train including a plu- 'ality of vehicles each equipped with automatic'train control apparatus, of a control relay on each vehicle for governing the operation of its corresponding apparatus, a circuit on the train connecting said relays for simultaneous operation, a source of current on the train, means for causing deenergization of the control relays and for establishing a connection between said source and said circuit, and a protective device controlled by said means for detecting the failure of any relay to be deenergized in response to the control of said means.

37. In an automatic train control system, the combination with a train including a plurality of vehicles each equipped with automatic train control apparatus, of a control relay on each vehicle adapted when energized to maintain the correspondingtrain. apparatus in its inactive condition, a circuit acting when supplied with current to cause simultaneous energization of said control relays, a-source' of current-on the train, means partly on the train and partly along the track acting under safe traffic conditions to establish a connection between said source and said circuit, and a protective device also controlled by said means and acting to detect the improper application of current to said circuit.

38. In an automatic train control system, the combination with a train including a number of vehicles each equipped with automatic train control apparatus, of a control relay on each vehicle adapted when deenergized to cause operation of its corresponding apparatus, said relays being electrically connected for simultaneous operation, means governed automatically in accordance with traffic conditions for causing said relays to be deenergized under dangerous traflic conditions, and a protective device on each vehicle controlled by said means and by the corresponding control relay, said protective device acting to detect a failure of its corresponding control relay to become deenergized under dangerous traffic conditions.

39. In an automatic train control system, the combination with a train including .t number of vehicles, of a control relay on each vehicle, a circuit and a source of current on the train for simultaneously energizing said relays, means for causing successive deenergization of said relays under dangerous traffie conditions and for establishing a connection between said circuit and said source of current under safe tratiic conditions, and means for detecting the failure of any relay to become deenergized under dangerous trattic conditions.

4-0. In an automatic train control systen'i, train control apparatus on a railway vehicle, means adapted to be influenced from the trackway for governing the operation of said apparatus. a separate projective device subjected to the same controlling influence as said apparatus and tending to change from a normal initial condition to an active condition, and means governed by said train control apparatus while operating for maintaining said protective device in its initial condition.

11. in an automatic train control system for railroads including car-carried automatic train .control apparatus adapted to have its operation influenced from the trackway. the combination with said train control appara tus. of an electrically operable slow-acting protective device on the car, a stick circuit torsaid device subjected to the same controlling influence as said train control apparatus, and a pickup circuit for said device established automatically while said train control apparatus is operating.

42. In an automatic. train control system for railway trains each including a number of vehicles similarly equipped. a control relay on each vehicle, a circuit connecting the control relays on the several vehicles tor simultaneous operation, means on each vehicle adapted to be influenced from the trackway for controlling the supply ot' current to said circuit, and a protective device on each vehicle subjected to the same controlling influence as the corresponding control relay.

-13. in an automatic train control system for railway trains each including a number of vehicles similarly equipped, a normally energized control relay on each vehicle. a circuit extending through the train and connecting the control relay on the several vehicles in multiple. impulse transmitting means for causing deencrgization of said control relays under dangerous tratiic donditions and for supplying current to said circuit under safe traliic conditions, and protective means on each vehicle subjected to the same controlling influence as the corresponding control relay for checking the deenergization of the corresponding control relay. whereby a failure of said circuit tending to improperly hold up a control relay will be detected.

4%. in an automatic train control system for railway trains each including a number of vehicles similarly equipped, a control relay on each vehicle, a normally closed energizing circuit tor each control relay. restoring means on the train for energizing said control relays simultaneously and independently of their respective normally closed circuits, tratiic controlled means partly on the vehicle and partly along the track for governing said restoring means in accordance with traiiic conditions, and protective means governed simultaneously in the same way as each control relay but independently of said restoring means for checkingthe operation of said control relay.

45. In an automatic train control system, the combination with a train including a number of vehicles. of automatic train con trol apparatus on the train. normally energized electromagnetic means on each vehicle for controlling the operation of said apparatus, a circuit connecting said electromagnetic means on the several vehicles for simultaneous energization without preventing their deenergization separately. at source of electrical energy on the train, impulse transmitting means acting when traffic conditions are safe to supply energy from said source to said circuit. and separate protective means governed in the same way. as each control relay independently of said circuit. whereby the operation of said control relay is checked.

46. An automatic train control system for railways comprising a plurality of automatic train control devices carried by several vehicles ot' a train and each adapted to control the train as a whole. a circuit for simultaneously controlling said train control devices, means partly on the vehicles and partly along the track and responsive to the presence of a train ahead for transmitting controlling impulses to the vehicles, a source of current on the train. means associated with each vehicle and governed by said last mentioned means for supplying current from said source to said circuit, and protective means "for checking the operation of said train control devices.

47. An automatic t 'ain control system for railways comprising a plurality of automatic train control devices carried by several vehicles of a train and each adapted to control the train as a whole. said devices having a tendency to assume an active controlling condition and being normally restrained in their inactive condition. means comprising cooperating elements partly on the vehicles and partly along the track tending to cause said train control devices to assume an active condition at different control points along the track. said means being adapted to transmit a controlling impulse to the vehicles under sate trattic conditions, means in part associated with each vehicle and responsive to said controlling impulses for simultaneously restoring the train controlling devices on the several vehicles to their inactive condition. and means on each vehicle subjected to the same controlling influence as'the corresponding train control device for checking the operation thereof.

48. An automatic train control system for railways comprising a plurality of automatic train controlling devices carried by several vehicles of a train and each adapted to control the train as a whole, means comprising cooperating elements partly on the vehicles and partly along the track for successively rendering said train control devices effective at control points along the track when dan-v gerous traflic conditions exist, said means also rendering said train control devices si multaneously ineffective at said control points when traflic conditions are safe, and means for detecting failure of the train control devices to become effective when controlled to do so.

49. In an automatic train control system for railway trains including a number of vehicles each similarly equipped with speed control apparatus adapted to govern the train as a whole, said speed control apparatus being adapted when set into operation to automatically enforce predeterminated speed restrictions, the combination with said speed control apparatus on the several vehicles, of means including conductors between the vehicles and protective devices for detecting crosses upon said conductors for restoring the speed control apparatus on the several vehicles simultaneously.

50. In an'automatic train control system for railways, a slow-acting device on a railway vehicle having a tendency to assume its ultimate condition and adapted to-apply the brakes of the vehicle when it attainsits ultimate condition, means adapted to be influenced from the trackway for setting said device into operation, and speed responsive means governed in accordance with the speed of the vehicle for preventing effective action of said slow-acting means when the speed of the vehicle is less than a predetermined speed.

51. In an automatic train control system for railways in which a railway vehicle is equipped with automatic train control apparatus, including a slow-acting protective device governed in the same way as said train control apparatus so as to check the operation thereof, the combination with said protective device, of speed responsive means .t'or nullifying the effective action of said protective device at slow speeds of the vehicle.

In an automatic train control system, a satiety appliance on a railway vehicle, two separate devices on the vehicle subjected to the same controlling influence and each capable of operating the safety appliance, and means controlled by one device when active for maintaining the other device inactive,

whereby the operation of one device is checked by the other.

53. In a system forprotecting railway traflic, in combination: a train including a number of vehicles; trafiic protecting mechanism carried by said train; a relay associated with each vehicle for governing said mechanism, said relay having two windings; a circuit controller operated by said relay and closed when either of said windings is energized; a normally closed circuit for normally energizing one of said windings and including said circuit controller; and a circuit for energizing said other windings of said relays on the respective vehicles simultaneously.

54. An automatic train control system for railways comprising a plurality of relays for interrupting the stick circuits of said re-- lays at control points along the track, a circuit for simultaneously energizing said relays independently of their, stick circuits, and means on eachvehicle controlled by said communicating means and rendered effective under safe'traific conditions for supplying current to said last mentioned circuit.

55. An automatic train control .system for railways comprising a plurality of relays carried by several vehicles of a train, each of said relays having two windings, astick circuit for each relay including one of its windings, a circuit for simultaneously supplying current to the other winding of each relay, and im ulse transmitting means comprising elements partly on each vehicle and partly along the track for supplying current to said last mentioned circuit under safe trailic conditions.

56. An automatic train control systemefor railways comprising a plurality of control relays on several vehicles of a train, each of said relays having two windings, a local stick circuit for each relay including one of .its windings, a circuit for simultaneously supplying current to the other winding of each relay, and impulse transmitting means associated with each vehicle and comprising elements partly on the vehicle and-partly along the track for interrupting the. corresponding stick circuit at control points along the track and for controlling the flow of current in the last mentioned circuit in accordance with traflic conditions.

57. An automatic train control system for railways comprising a plurality of control relays on several vehicles of a train, each of said relays having two windings, a local stick circuit for each relay including one of its windings, an energizing circuit adapted to supply current simultaneously to the other windings of said relays, a second relay on each vehicle, means acting upon energization of any second relay to supply current to said energizing circuit, means for inter rupting the stick circuits on the several vehicles successively at control points along the track, and means for controlling the energization of the second relay on a vehicle at said control points in accordance with trafhc conditions.

58. Car equipment for train control systems comprising, brake control apparatus, a protective device subjected to the same controlling influence as said apparatus and operable separately therefrom, said device when operated causing an automatic brake application, and means effective while the apparatus is operating to prevent operation of the protective device.

59. bar equipment for train control systems comprising, brake control apparatus, a. protective device tending to change to an ultimate condition and cause a brake application, means adapted to be influenced from the trackway for governing said apparatus and device in the same way, and means efiective while the apparatus is operating to prevent operation of the protective device.

60. Car equipment for train control systems comprising, a brake control apparatus, and a separate and independently operable protective device'subjected to the same con- --trolling influence as said apparatus and hav- Ml ing its operation dependent upon the operating condition of said apparatus.

61. Car equipment for train control systems comprising, speed governed brake control apparatus on a vehicle, a protective device acting when operated to cause a brake application and automatically maintained in its inactive condition while the apparatus is operating, and means adapted to be fiuenced from the trackway for governing the apparatus and protective device simultaneously in the same manner.

62. In a train control system, the combination with automatic mechanism on a vehicle for "governing the movement thereof, means partly on the vehicle and partly on the track for controlling the operation of said mechanism in accordance with trafiic a changed condition when said apparatus is operating, and a separate device operable independently of the apparatus but subjected to the same governing influence for detecting failure of the apparatus, said.device being automatically held in its normal inactive condition while said changeable means is in its changed condition.

6 In a train control system, the combi-' nation with speed governed train control apparatus on a vehicle including an element shifted when the apparatus is operating, a protective device adapted when operated to cause a brake application independently of said apparatus, means for maintaining said device in its normal inactive condition while said element is shifted, and means partly on the vehicle and partly on the track for simultaneously influencing said apparatus and said device in the same way dependent upon traiiic conditions.

65. in a train control system, brake control apparatus on a vehicle, means partly on the vehicle and partly on the track for governing the operation of said apparatus in accordance with traflic conditions, and automatic means for checking operation of said apparatus, said automatic means being set into operation under dangerous trafiic conditions by the influence of said first mentioned means but being maintained inactive when the apparatus assumes its effective operating condition.

66. In a train control system, the combination with a brake setting appliance on a vehicle, of separately operable train control apparatus and protective means subjected to the same control from the trackwav and each capable of actuating said appliance, said protective means being automatically maintained inactive while the train control apparatus is operating. 67. In a train control system, separate and independently operable devices on a vehicle each capable of controlling the brakes thereof, one of said devices when operated preventing operation of the other, and means partly on the vehicle and partly on the track for simultaneously governing said devices in the same way in accordance with trafiic conditions, whereby the operation of one device serves to checkthe operation of the other.

68. In a train control system, a brake con trolappliance on a vehicle, separate and in dependently operable devices on the vehicle each having a pick-up and a stick circuit and each capable of actuating said appliance, one of said devices when in the operating condition preventing the operation of the other, and cooperating elements on the vehicle and on the trackway for controlling the circuits of said devices simultaneously in the same way.

69. A train control system comprising, two separate and independently operable devices Mill 

